This proposal relates to a unique area of microbiology which is the isolation and fermenting of the black yeast. These yeast-like fungi (Pullularia) are normally associated with the phyllosphere. The investigator is considered the world's expert in black yeast and is well known for his fermentation and chemical isolation abilitites. The black yeast are known to produce water soluble polyglucans and also lipases, lipids, and glycolipids. The isolating, maintaining, and growing of the black yeast is the first phase. The second phase involves the fermentation chemistry. The polymers will be isolated and tested for antineoplastic activity (especially solid tumors). The broths after removal of the polymers will be tested for antineoplastic activity and those found active will have the active compounds isolated. Preliminary research indicates that the novel polyglucans obtained from the black yeast cell walls interact with the cell membrane receptors of neoplastic cells which might indicate the possibility of a selective chemotherapeutic approach.